Multiple Material Iron-Type Golf Club Head

ABSTRACT

A golf club head includes a perimeter member made of high density material and a face plate insert made of lower density material. In one embodiment, the face plate insert is formed by applying a shell member to a core member so that the shell member encases the core member. Preferably, the shell member is made by electrodepositing a nanometal having a grain size between 10 and 50 nanometers onto the core member.

BACKGROUND OF THE INVENTION

This invention relates generally to golf equipment and, in particular,to golf club heads.

Iron-type golf clubs are intended primarily for second and later shotsrather than tee shots. Often they are used for hitting shots from bareground or sand as well as from turf. Accordingly, conventional iron-typegolf clubs are designed so that the club head and, in particular, thesole of the club head are made of a durable material such as iron,stainless steel or like. It is generally desirable for an iron-type golfclub head to have perimeter weighting to increase its moment of inertiato resist twisting. It is also desirable for an iron-type golf club headto have a low center of gravity to enhance the ability of the club headto launch the golf ball in an appropriate trajectory and for the clubhead to be forgiving on off-center hits. Conventional iron-type golfclubs accomplish some of these goals through the use of cavity back clubheads, tuning ports in the club heads and, more recently, lightweightforged or rolled titanium club head faces attached to heavier perimetermembers.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a golf club head incorporatingfeatures of the present invention;

FIG. 2 is a cross-sectional view of one embodiment of a face plateinsert according to the present invention;

FIG. 3 is a cross-sectional view of the club head of FIG. 1 taken alongline 3-3;

FIG. 4 is a cross-sectional view, similar to FIG. 2, of anotherembodiment of the face plate insert; and

FIG. 5 is a cross-sectional view, similar to FIG. 3, of a club headincluding the face plate insert of FIG. 4.

DESCRIPTION OF THE INVENTION

The drawing figures are intended to illustrate the general manner ofconstruction and are not necessarily to scale. In the detaileddescription and in the drawing figures, specific illustrative examplesare shown and herein described in detail. It is understood, however,that the drawing figures and the detailed description are not intendedto limit the invention to the particular form disclosed, but are merelyillustrative and intended to teach one of ordinary skill how to makeand/or use the invention claimed herein and for setting forth the bestmode for carrying out the invention.

With reference to FIGS. 1-3, an iron golf club head 10 incorporatingfeatures of the present invention is preferably composed of two maincomponents, a perimeter member 12 and a face plate insert 14. Theperimeter member 12 is preferably composed of a relatively densematerial such as stainless steel, carbon steel, beryllium-copper, orother material having a density of least 7.0 grams per cubic centimeter.The perimeter member has a sole wall 16, a heel wall 18 extendingupwardly from heel end 20 of sole wall 16, a toe wall 22 extendingupwardly from toe end 24 of sole wall 16, and a top wall 26 extendingfrom an upper end 28 of heel wall 18 to an upper end 30 of toe wall 22.Perimeter member 12 further comprises a hosel 32 having a hosel bore 34for receiving a golf club shaft (not shown).

Face plate insert 14 is preferably formed of a core member 36 and ashell member 38 that encases core member 36. Preferably, core member 36is composed of a material such as aluminum, thermoplastic,thermosetplastic or foam metal having a bulk density of less than 2.7grams per cubic centimeter. Core member 36 is preferably a solid prismhaving substantially the same shape as finished face plate insert 14 butsmaller in overall size. Core member 36 preferably has a thickness alpha(a) in the range of 0.025 to 0.040 inches, and preferably between 0.035and 0.040 inches.

Shell member 38 comprises a metallic coating that fully encases coremember 36. Preferably, shell member 38 comprises a nickel iron nanometalhaving a grain size on the order of 10 to 50 nanometers. Shell member 38comprises a front wall 40, a rear wall 42 and a perimeter wall 44. Frontwall 40 has a front surface 47 arranged for impacting a golf ball.Preferably, front wall 40 has a thickness beta (β) between 0.030 and0.050 inch, rear wall 42 has a thickness gamma (γ) between 0.015 and0.025 inch, and perimeter wall 44 preferably has a thickness delta (δ)between 0.015 to 0.030 inch.

Shell member 38 may be sintered onto core member 36 to form face plateinsert 14, however, shell member 38 is preferably applied to core member36 by an electroplating or electroforming process such as theelectroplating process for applying nanometals practiced by Power MetalTechnologies, Inc. of Carlsbad, Calif. This process applies coatingsthat are in excess of 0.010 inches in thickness as opposed toconventional chrome and other protective coatings which are typicallyless than 0.001 inch thick or less than 1% of the thickness of the partbeing coated. All of the thicknesses β, γ and δ are at least 1% asthick, and preferably at least 10% as thick, as the thickness α of coremember 36. As can be determined from an examination of FIG. 2, faceplate insert 14 has an exceptionally high area moment of inertia as aresult of the displacement between front wall 40 and rear wall 42.Consequently, a face plate insert constructed in accordance with theteachings of the present invention is lighter, stiffer and yet moreforgiving than prior art face plate inserts.

Face plate insert 14 further includes a plurality of grooves 46 disposedin front wall 40. Grooves 46 are preferably U-shaped in cross-sectionwith substantially vertical walls meeting the front surface 47 of faceplate insert 14 along a fillet having a radius of 0.010±0.001 inch.Because front wall 40 is formed by an electrodeposition process, ratherthan casting, the tolerance on the U-shaped grooves 46 can be held tothese close tolerances without the necessity of secondary machining.

As shown in FIG. 3, face plate insert 14 may be attached to perimetermember 12 by any conventional means but in the illustrative embodimentis attached to perimeter member 12 by placing face plate insert 14 intoa recess 48 formed in perimeter member 12 until it comes to rest againstledge 50. Recess 48 is formed by the sole, heel, toe and top walls 16,18, 22 and 26, respectively, of perimeter member 12. A deformable lip 52is then deformed until it presses against shell front wall 40 to form acrimp joint that permanently retains face plate insert 14 in place. Faceplate 14 may, however, be attached by unconventional means such asnanobonding in which dissimilar metals are bonded on a submicroscopiclevel.

Referring to FIGS. 4 and 5, the face plate insert 14 has been replacedby a face plate insert 14A. It will be understood that, in the faceplate insert 14A, the core member 36A is sandwiched between front andrear walls 40A, 42A of a shell member 38A. The perimeter wall 44 of theface plate insert 14 has been removed from the face plate insert 14A.

Although certain illustrative embodiments and methods have beendisclosed herein, it will be apparent from the foregoing disclosure tothose skilled in the art that variations in modifications of suchembodiments and methods may be made without departing from the spiritand scope of the invention. For example, although the illustrativeembodiment discloses a single solid core, multiple cores and/or hollowcores are considered within the scope of the invention. Accordingly, itis intended that the invention should be limited only to the extentrequired by the appended claims and the rules and principles ofapplicable law.

1. A golf club head comprising: a perimeter member including a solewall, a heel wall extending upward from a heel end of said sole wall, atoe wall extending upward from a toe end of said sole wall, and a topwall extending from an upper end of said heel wall to an upper end ofsaid toe wall; said heel, toe, sole and top walls cooperating to form arecess; and a face plate insert received in said recess and attached tosaid perimeter member, said face plate insert including a core memberhaving a first predetermined thickness and a shell member encasing saidcore member, said shell member having a second predetermined thicknessthat is at least 1% as thick as the first predetermined thickness, saidshell member having a front surface arranged for impacting a golf ball.2. The golf club head of claim 1, wherein the second predeterminedthickness is at least 10% as thick as the first predetermined thickness.3. The golf club head of claim 1, wherein said perimeter member is madeof a first material having a first density and wherein said core memberis made of a second material having a second density that is less thansaid first density.
 4. The golf club head of claim 1, wherein said coremember is made of nonmetallic material.
 5. The golf club head of claim1, wherein said core member is made of metallic material.
 6. The golfclub head of claim 1, wherein said shell member is made of a nanometalhaving a grain size between 10 and 50 nanometers.
 7. The golf club headof claim 6, wherein the nanometal is electrodeposited onto the coremember.
 8. The golf club head of claim 6, wherein the nanometal issintered onto the core member.
 9. The golf club head of claim 1, whereinsaid shell member comprises a front wall having a thickness between0.030 and 0.050 inch.
 10. The golf club head of claim 9, wherein saidshell member comprises a rear wall having a thickness between 0.015 and0.025 inch.
 11. The golf club head of claim 10, wherein said shellmember comprises a perimeter wall having a thickness of at least 0.015inch.
 12. The golf club head of claim 1, wherein said face plate insertis attached to said perimeter member by a crimp joint.
 13. The golf clubhead of claim 1, wherein: the front surface of said shell member has aplurality of U-shaped grooves formed therein; and each of said U-shapedgrooves has a first side wall and a second side wall, said first andsecond side walls intersecting said front surface along a fillet havinga radius of 0.010 inch held to a tolerance of ±0.001 inch.
 14. A methodof manufacturing a golf club head comprising: providing a perimetermember made of a first material having a first density, said perimetermember having a sole wall, a heel wall extending upward from said solewall, a toe wall extending upward from said sole wall, and a top wallextending from an upper end of said heel wall to an upper end of saidtoe wall, said heel, toe, sole and top walls cooperating to form arecess; forming a core member from a second material having a seconddensity that is less than said first density, said core member having apredetermined thickness; encasing said core member in a shell member toform a face plate insert, said shell member having a predeterminedthickness that is at least 1% as thick as said predetermined thicknessof said core member, said shell member further including a front surfacearranged for impacting a golf ball; mounting said face plate insert insaid recess; and attaching said face plate insert to said perimetermember.
 15. The method of claim 14, wherein the core member is made ofnon-metallic material.
 16. The method of claim 14, wherein the shellmember is made of nanometal having a grain size between 10 and 50nanometers.
 17. The method of claim 16, wherein the nanometal is appliedby electrodeposition.
 18. The method of claim 16, wherein the nanometalis applied by sintering.
 19. The method of claim 14, further comprisingforming a plurality of grooves in the front surface of the shell memberwith each of the grooves having a U-shaped cross section with a firstside wall and a second side wall, said first and second side wallsintersecting said front surface along a fillet having a radius of 0.010inch held to a tolerance of ±0.001 inch.
 20. The method of claim 14,wherein attaching said face plate insert to said perimeter membercomprises using a crimp joint formed by deforming a lip on saidperimeter member against the shell front surface.
 21. The golf club headof claim 3, wherein said first density is at least 7.0 grams per cubiccentimeter and wherein said second density is less than 2.7 grams percubic centimeter.
 22. The method of claim 14, wherein said first densityis at least 7.0 grams per cubic centimeter and wherein said seconddensity is less than 2.7 grams per cubic centimeter.
 23. A golf clubhead comprising: a perimeter member including a sole wall, a heel wallextending upward from a heel end of said sole wall, a toe wall extendingupward from a toe end of said sole wall, and a top wall extending froman upper end of said heel wall to an upper end of said toe wall; saidheel, toe, sole and top walls cooperating to form a recess; and a faceplate insert received in said recess and attached to said perimetermember, said face plate insert including a core member having a firstpredetermined thickness and a shell member, said core member beingsandwiched between front and rear walls of said shell member, said shellmember having a second predetermined thickness that is at least 1% asthick as the first predetermined thickness, said shell member front wallhaving a front surface arranged for impacting a golf ball.
 24. The golfclub head of claim 23, wherein the second predetermined thickness is atleast 10% as thick as the first predetermined thickness.
 25. The golfclub head of claim 23, wherein said perimeter member is made of a firstmaterial having a first density and wherein said core member is made ofa second material having a second density that is less than said firstdensity.
 26. A method of manufacturing a golf club head comprising:providing a perimeter member made of a first material having a firstdensity, said perimeter member having a sole wall, a heel wall extendingupward from said sole wall, a toe wall extending upward from said solewall, and a top wall extending from an upper end of said heel wall to anupper end of said toe wall, said heel, toe, sole and top wallscooperating to form a recess; forming a core member from a secondmaterial having a second density that is less than said first density,said core member having a predetermined thickness; sandwiching said coremember between front and rear walls of a shell member to form a faceplate insert, said shell member having a predetermined thickness that isat least 1% as thick as said predetermined thickness of said coremember, said shell member front wall further including a front surfacearranged for impacting a golf ball; mounting said face plate insert insaid recess; and attaching said face plate insert to said perimetermember.